Typing or printing is usually performed serially by character on a line by line basis, each line extending on the record medium (sheet of paper) between left and right margins. When typing any language that reads from left to right, the typewriter is usually provided with means for automatically starting the typing at a fixed distance from the left edge of the record medium. The left margin will therefore be easily made parallel to that edge without requiring any further attention from the typist. However, because the number of characters in a print line may vary, the right margin will usually not be made automatically settable. Attention is required from the typist who will have a certain lattitude of adjustments for positioning the last character typed on each line. Conventional typewriters are usually provided with a bell which rings when the extreme right limit for printing is close to being reached, to call for the attention of the typist. The bell is generally bulky and relatively expensive and it would be desirable from a designer's point of view to avoid the needs for such a device and still provide means for performing the bell function.